Wearable biosignal interface and method thereof

ABSTRACT

A wearable biosignal interface and operation method of the wearable biosignal interface is provided wherein the wearable biosignal interface may perceive a motion unintentionally performed by a user and ignore a biosignal obtained thereby and thus, improve accuracy of a bio-based determination of an intention of the user for operating a device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage Application of InternationalApplication No. PCT/KR2014/004073, filed on May 8, 2014, which claimsthe benefit under 35 USC 119(a) of Korean Patent Application No.10-2013-0098476 filed on Aug. 20, 2013, in the Korean IntellectualProperty Office, the entire disclosure of which is incorporated hereinby reference for all purposes.

BACKGROUND

1. Field

The following description relates to a wearable biosignal interface andan operation method thereof, and to an apparatus for controlling anexternal device and a method of controlling an external device using awearable apparatus.

2. Description of Related Art

Recently, wearable-type mobile devices are emerging at an acceleratedrate amid the proliferation of smartphones. A wearable-type mobiledevice may include a separate screen for displaying information obtainedby a smartphone through a wireless data network, allowing its user toprocess data without directly viewing the screen of the smartphone.

A gesture recognized by an accelerometer or a biosignal sensor may beused to operate the wearable mobile device. However, operating thewearable mobile device based only on the gesture may increase aprobability of misrecognizing the intention of the user. For example, ina wearable mobile device designed to be operated by recognizing a handgesture, a movement of the arm connected to the hand may be recognizedas a hand gesture, misinterpreting the intention of the user inoperating the wearable mobile device.

Accordingly, a wearable mobile device model that recognizes an intentionof a user with a greater precision is desirable to improve userexperience.

SUMMARY

In one general aspect, there is a provided a wearable biosignalinterface including a motion sensor configured to obtain a first signalbased on a motion of a target, a biosignal sensor disposed on the targetand configured to obtain a second signal from the target, and adetermination controller configured to determine a validity of thesecond signal based on the first signal.

The second signal may include biological information obtained by one ormore biosensor in contact with skin of the target.

The determination controller may be configured to determine the secondsignal to be valid in response to a magnitude of the first signalsatisfying a first threshold value.

The determination controller may be configured to identify an intervalduring which a magnitude of the first signal is less than or equal to afirst threshold value and to determine a signal, among a plurality ofsecond signals obtained by the biosignal sensor in the identifiedinterval, to be a valid second signal.

The determination controller may be configured to determine the firstthreshold value based on a magnitude of the second signal.

The determination controller may be configured to determine the secondsignal to be invalid, irrespective of the first signal, in response tothe magnitude of the second signal not satisfying a second thresholdvalue.

In response to a determination that the second signal is valid, thedetermination controller may be configured to operate in an active modeand to control an external device based on the second signal.

In another general aspect, an operation method of a wearable biosignalinterface may involve using a motion sensor to obtain a first signalbased on a motion of a target, using a biosignal sensor disposed on thetarget to obtain a second signal, and determining a validity of thesecond signal based on the first signal.

The second signal may include biological information obtained by one ormore biosensor in contact with skin of the target.

The determining of the validity may involve determining the secondsignal to be valid in response to a magnitude of the first signalsatisfying a first threshold value.

The determining of the validity may involve identifying an intervalduring which a magnitude of the first signal is less than or equal to afirst threshold value, and determining a signal, among second signalsobtained by the biosignal sensor in the identified interval, to be avalid second signal.

The determining of the validity may further include determining a firstthreshold value based on a magnitude of the second signal.

The determining of the validity may involve determining the secondsignal to be invalid, irrespective of the first signal, in response to amagnitude of the second signal not satisfying a second threshold value.

The general aspect of the method may further involve operating in anactive mode and controlling an external device based on the secondsignal, in response to the second signal being determined to be valid.

In another general aspect, an apparatus including a motion sensorconfigured to detect movement of a target, a second sensor configured todetect biological information of the target, and a controller configuredto determine an interval of stability from the movement of the targetdetected by the motion sensor, to determine whether a magnitude of abiological signal obtained during the interval is less than or equal toa first threshold value, and to identify a command for controllinganother device in response to the magnitude being less than or equal tothe first threshold value.

The interval may be determined by extracting a first processed signalfrom the detected movement of the target, and the biological signal maybe obtained by extracting a second processed signal from the biologicalinformation obtained by the second sensor, the second sensor comprisingone or more biosensor.

The interval may correspond to a time duration in which a magnitude ofthe first processed signal is less than or equal to a second thresholdvalue.

The general aspect of the apparatus may further include a transmissionunit configured to transmit the command to the another device, and thedetermination controller may be configured to identify the command basedon the second processed signal.

In response to a determination that the magnitude of the biologicalsignal is greater than the first threshold value, the apparatus may beconfigured not to transmit a command based on the biological informationobtained during the interval.

Other features and aspects will be apparent from the following detaileddescription, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an example of a wearable biosignalinterface.

FIG. 2A through FIG. 2D are diagrams illustrating an example of a methodof determining the validity of a signal based on a first signal and asecond signal.

FIG. 3 is a diagram illustrating an example of a method of performing acommand given to an external device, using a magnitude of a first signaland a magnitude of a second signal.

FIG. 4 is a flowchart illustrating an example of a method of operating awearable biosignal interface.

Throughout the drawings and the detailed description, unless otherwisedescribed, the same drawing reference numerals will be understood torefer to the same elements, features, and structures. The relativemagnitude and depiction of these elements may be exaggerated forclarity, illustration, and convenience.

DETAILED DESCRIPTION

The following detailed description is provided to assist the reader ingaining a comprehensive understanding of the methods, apparatuses,and/or systems described herein. Accordingly, various changes,modifications, and equivalents of the methods, apparatuses, and/orsystems described herein will be suggested to those of ordinary skill inthe art. The progression of processing steps and/or operations describedis an example; however, the sequence of and/or operations is not limitedto that set forth herein and may be changed as is known in the art, withthe exception of steps and/or operations necessarily occurring in acertain order. Also, description of well-known functions andconstructions may be omitted for increased clarity and conciseness.

The features described herein may be embodied in different forms, andare not to be construed as being limited to the examples describedherein. Rather, the examples described herein have been provided so thatthis disclosure will be thorough and complete, and will convey the fullscope of the disclosure to one of ordinary skill in the art.

As described herein, a sensor may refer to a sensor or a plurality ofsensors that may be attached to a target to be in contact therewith ordisposed thereon so as to obtain a signal generated from the target orto detect a motion of the target.

For example, a sensor may include a biosensor that may be attached to abody part of a living being or living organism such as, for example, awrist or a forearm of a person, in order to obtain a biological orphysiological signal. For example, a biosensor may be able to detectsignals generated by muscle contraction or muscle relaxation of a bodypart, such as a wrist or a heart. Herein, such a sensor may refer to asa biosignal sensor. A biosignal sensor may detect biological informationfrom a target and may convert the biological information into a signalwaveform to generate a biosignal. Such a biosignal sensor may include aphoto sensor, a piezoelectric sensor, a force sensor, an electromyogram(EMG) sensor, and the like.

Herein, a muscle may refer to a striated muscle, a cardiac muscle or asmooth muscle, and may refer to a muscle group, a number of musclegroups in a body region, bundles of muscle fibers and the like. Forinstance, an arm may include several different muscle groups, includinga tricep, a bicep and a brachioradialis.

A sensor may include an acceleration sensor, a gyro sensor, ageomagnetic sensor, and a Global Positioning System (GPS) sensor. Such asensor may directly or indirectly monitor a motion performed by theliving target and may obtain a signal associated with the motionperformed by the living target. Hereinafter, the sensor described abovewill be referred to as a motion sensor.

To control an external device using a biosignal obtained by a biosignalsensor, an example of a wearable biosignal interface may ignore abiosignal in the event that a magnitude of a signal associated with amotion of a target exceeds a threshold value. Conversely, the wearablebiosignal interface may receive the biosignal in the event that themagnitude of the signal associated with the motion of the target is lessthan or equal to the threshold value.

The wearable biosignal interface may make a determination as to whethera motion is unintentionally or spontaneously made by a user, and mayignore a biosignal obtained as a result of the unintentional orspantaneous motion. Using this approach, the accuracy of determinationregarding the intention of the user may be improved.

FIG. 1 is a diagram illustrating an example of a wearable biosignalinterface 100.

Referring to FIG. 1, the example of the wearable biosignal interface 100include a motion sensor 110, a biosignal sensor 120, a determinationcontroller 130, and a transmission unit 140.

The motion sensor 110 may detect a motion of a target 105 and may obtaina first signal. For instance, the first signal may include anacceleration signal, a rotation signal, a bearing signal, and acoordinate signal. These signals may be associated with velocityvariance based on a motion of the target 105.

The motion sensor 110 may monitor a motion of the target 105 and mayreceive the first signal recognizing a movement of the wearablebiosignal interface 100 associated with the motion. Also, the motionsensor 110 may identify a gesture performed by the target 105 byobtaining a second signal after obtaining a first signal associated withan identified gesture.

The motion sensor 110 may include, for example, an acceleration sensor.Such a motion sensor 110 may convert an acceleration signalcorresponding to the obtained first signal into a velocity component bycalculating an integral of the acceleration signal. The motion sensor110 may determine one or more numerical values indicating a magnitude ofa motion of the target 105.

In the event that the target 105 is an arm that is flexed in anydirection, the motion sensor 110 may obtain a first signal associated an“arm motion” based on the flexing. Also, the motion sensor 110 maymeasure a magnitude of the obtained first signal and may measure amagnitude of a velocity of the “arm motion.”

The motion sensor 110 may include a gyrosensor. Using a gyrosensor, sucha motion sensor 110 may detect a rotation signal corresponding to thefirst signal.

The target 105 may be an arm. In the event that the arm performs a largerotation motion, the motion sensor 110 may obtain a first signalassociated with the “arm rotation” based on the rotating motion of thearm. In addition, the motion sensor 110 may measure a magnitude of theobtained first signal and may measure a magnitude of a rotationalvelocity of the “arm rotation.”

The motion sensor 110 may include a geomagnetic sensor or a GPS sensor.Using the geomagnetic sensor or the GPS sensor, such a motion sensor 110may detect a bearing signal or a coordinate signal corresponding to thefirst signal.

The motion sensor 110 may be fixed to a form of a bracelet fastened ontothe target 105, along with the biosignal sensor 120.

The biosignal sensor 120 may be in contact with the target 105 and mayobtain a second signal from the target 105. In the illustrated example,the biosignal sensor 120 directly contact the skin of the target 105.However, in another example, the biosignal sensor 120 may be disposed onthe target 105 indirectly, such as through a clothing that covers theskin. The second signal may be a biosignal associated with biologicalinformation such as, for example, muscle contraction and musclerelaxation occurring in the target 105. The second signal may be abio-electric/magnetic signal, a bio-impedance signal, and abio-mechanical signal generated in association with a muscle.

The biosignal sensor 120 may be in contact with the target 105 and mayobtain the second signal generated by at least one of muscle contractionand muscle relaxation. In the event that the target 105 is a wrist, thebiosignal sensor 120 may detect the second signal generated by themuscle contraction or muscle relaxation of the wrist.

The target 105 may be a wrist, a forearm, a face, a neck, or the like ofa living being, and a muscle that generates a second signal may belocated within the portion of body.

The biosignal sensor 120 may include at least one biosensor that maydetect the second signal from a muscle of the target 105, and maymonitor the contraction or relaxation of the muscle using the at leastone biosensor. The biosensor may be a photo sensor, a piezoelelctricsensor, a force sensor, an electromyogram (EMG) sensor, and the like.

For example, the biosignal sensor 120 may include the photo sensor.Using the photo sensor, such a biosignal sensor 120 may obtain thesecond signal associated with a status of the target 105, based on lightscattering.

The biosignal sensor 120 may include a piezoelelctric sensor or a forcesensor. Using a piezoelelctric sensor or a force sensor, such abiosignal sensor 120 may obtain a second signal associated with anextension and/or contraction of a muscle of the target 105.

The biosignal sensor 120 may include an EMG sensor. Using an EMG sensor,a biosignal sensor may obtain a second signal associated with the musclecontraction or relaxation of a heart muscle of a target 105.

The biosignal sensor 120 may be fixed to the bracelet fastened onto thetarget 105, along with the motion sensor 110. A sensing surface of thebiosignal sensor 120 may be fixed to the bracelet to be in a directcontact with the target 105. On the sensing surface, the at least onebiosensor may be arranged to detect the second signal generated from atarget 105. Using the biosignal sensor 120, the bracelet may broadlydetect a second signal such as the bio-electric/magnetic signal, thebio-impedance signal, and the bio-mechanical signal over an area of thebody of the target 105.

The bracelet may be fastened onto the target 105 by being wrapped arounda wrist muscle over the skin, for example. The bracelet may be fastenedonto the target 105 by covering the wrist muscle with an area of thebracelet, for example, the sensing surface, in which one or morebiosignal sensor 120 is arranged. Using one or more biosensors, thebiosignal sensor 120 may collect a second signal from throughout anentire area of the wrist muscle of the target 105.

The determination controller 130 may determine a validity of the secondsignal based on the first signal. The determination controller 130 maydetermine whether the second signal obtained using the biosignal sensor120 is generated from the target 105 due to an intentional motion or amotion incidentally generated from the target 105 due to anunintentional or spontaneous motion made irrespective of an intention ofa user to operate an external device.

The determination controller 130 may determine the second signal to bevalid when a magnitude of the first signal satisfies a first thresholdvalue.

The first threshold value may be a reference value used to determine theintentional motion of the target 105. The first threshold value may bedetermined as an average value of magnitudes of first signals obtainedwhen the user moves a muscle for an actual operation.

The determination controller 130 may determine the first threshold valuebased on a magnitude of the second signal to be obtained. Thedetermination controller 130 may determine the first threshold value foran operation involving a large motion of the target 105 to be greater inproportion to the magnitude of the second signal. Accordingly, thesecond signal generated by an intentional motion may not be ignored dueto a low threshold value.

For example, the determination controller 130 may determine the firstthreshold value for a quick display shift operation of a displayapparatus for which a relatively greater second signal is generated tobe greater than the first threshold value for an ON/OFF operation of anillumination apparatus for which a relatively smaller second signal isgenerated.

To determine a validity of a second signal, the determination controller130 may identify an interval during which the magnitude of the firstsignal is less than or equal to the first threshold value and maydetermine a signal, among the second signals obtained during theidentified interval, to be a valid second signal. The determinationcontroller 130 may determine, to be valid, the second signal obtained inthe interval during which the magnitude of the first signal is less thanor equal to the first threshold value and a small motion of the target105 is performed.

In the event that the magnitude of the second signal does not satisfy asecond threshold value, the determination controller 130 may determinethe second signal to be invalid, irrespective of the first signal. Thesecond threshold value may be a reference value used to determine asecond signal that is valuable as information. The second thresholdvalue may be set as an averaged minimum value obtained based on dataobtained by simulations in which users moved their muscles to initiatean actual operation.

In response to the magnitude of the second signal being less than orequal to the determined second threshold value, the determinationcontroller 130 may determine whether the target 105 moves intentionallyor unintentionally to be indefinite and invalidate the second signal.Conversely, in response to the magnitude of the second signal beinggreater than the determined second threshold value, the determinationcontroller 130 may further determine whether the magnitude of the firstsignal satisfies the first threshold value and may determine thevalidity of the second signal.

Based on the determination, the determination controller 130 may operatein an active mode in response to the second signal being determined tobe valid and may allow an external device to be controlled based on thesecond signal.

An external device may refer to a device controlled by a command signal,such as a mobile device, a television (TV) screen, a digital versatiledisc (DVD) player, a radio, a heating thermostat, a vehicle door, andthe like. The command signal may be generated in association with avalid second signal of the wearable biosignal interface 100.

In the event that the magnitude of the first signal is less than orequal to the first threshold value and the magnitude of the secondsignal is greater than the second threshold value, the determinationcontroller 130 may shift a mode of the wearable biosignal interface 100to the active mode and may allow the external device to be controlledbased on the second signal. Thus, the accuracy of determining anintention of a user to operate the device may be improved.

To control the external device after the shift to the active mode, thewearable biosignal interface 100 may transmit the command signal basedon the second signal determined to be valid to an appliance or a devicein order to enable the external device to perform a control operation,using the transmission unit 140. For example, the wearable biosignalinterface 100 may transmit a command signal to an appliance such as aTV, an air conditioner, a computer, a refrigerator, and the like, or toa living environment controlling device such as a light, a curtain, awindow, a door lock device, and the like. The signal transmission mayenable the external device to perform a control operation of theappliance or device such as an ON/OFF operation, an open/closeoperation, and the like, in accordance with the command signal.

In another example, the wearable biosignal interface 100 may use a validsecond signal (or a second signal determined to be valid) as a signal ofa remote controller of a vehicle to start the vehicle or as an ID signalto make a payment.

In yet another example, the wearable biosignal interface 100 may use thevalid second signal for an interaction control with a computer, or asignal to edit a file stored on the computer or to move a page for apresentation.

The wearable biosignal interface 100 may detect and invalidate abiosignal generated by the unintentional motion of the target 105; thus,the wearable biosignal interface 100 may optimally avoid a control errorfor the external device.

The wearable biosignal interface 100 may identify a biosignal generatedonly when the target 105 is under a certain level of stability, and mayuse the biosignal obtained during the stable condition to control anexternal device; thus, the wearable biosignal interface 100 may providea precise determination of the user's intention for operating theexternal device.

FIG. 2A through FIG. 2D are diagrams illustrating examples of methods ofdetermining a second signal as a valid signal based on a first signaland a second signal.

FIG. 2A is a diagram illustrating an example of a first signal obtainedusing a motion sensor 110 of FIG. 1 of a wearable biosignal interface100 of FIG. 1. When a target 105 of FIG. 1 performs a rapid motion, suchas a motion of flexing an arm, in a interval from t₂ to t₃, the motionsensor 110 may obtain the first signal having a magnitude measured to begreat in the interval from t₂ to t₃. The first signal obtained in theinterval from t₂ to t₃ may be greater than a first threshold value usedas a reference value to determine an intentional motion of the target105.

FIG. 2B is a diagram illustrating an example of a second signal obtainedby a biosignal sensor 120 of FIG. 1 of a wearable biosignal interface100 of FIG. 1. As illustrated in FIG. 2B, the obtained second signal maybe in a form of an analog sine waveform and may have a greater waveformin a interval from t₁ to t₃ during which muscles of an arm are tense dueto the flexing of the arm.

FIG. 2C is a graph illustrating an example in which a determinationcontroller 130 of FIG. 1 of a wearable biosignal interface 100 of FIG. 1processes magnitudes of the obtained second signals and compares themagnitudes. The determination controller 130 may plot, based on thesecond signal of FIG. 2B, a parabola in which an inclination increasesdrastically after a point t₁ at which a waveform becomes larger and theinclination decreases drastically after a point t₃ at which the waveformbecomes smaller.

The second signal in the interval from t₁ to t₃ may be obtained whensatisfying a second threshold value used as a reference value todetermine a second signal that is valuable as information.

FIG. 2D illustrates an example of a method of determining, by adetermination controller 130 of FIG. 1, a validity of a second signalbased on a first signal and a second signal.

The determination controller 130 may invalidate the second signalobtained in the interval from t₂ to t₃ in which the first signalexceeding the first threshold value is obtained. Also, the determinationcontroller 130 may invalidate the second signal obtained during aninterval before t₁ and after t₃ during which the second signal less thanor equal to the second threshold value is obtained.

As shown in FIG. 2D, the determination controller 130 may determine thesecond signal obtained in of the interval from t₁ to t₂ to be a validsignal and may enable a command signal to be generated to control anexternal device during the interval.

The wearable biosignal interface 100 may operate, using the secondsignal, an external device such as a mobile device, a TV screen, a DVD,a radio, a heating thermostat, a vehicle door, and the like. Thewearable biosignal interface 100 may allow the operation of the externaldevice, using the second signal, only when the magnitude of the firstsignal decreases to be less than or equal to the first threshold valuedue to a small motion performed by a user in order to improve theaccuracy of the wearable biosignal interface 100 in determining anintention of a user for operation.

The wearable biosignal interface 100 may also allow the operation of theexternal device in response of the magnitude of the second signalsatisfying the second threshold value, indicating that the second signalincludes valuable information.

FIG. 3 is a diagram illustrating an example of a method of performing acommand given to an external device, using a magnitude of a first signaland a magnitude of a second signal.

Referring to FIG. 3, in 311, a motion sensor of a wearable biosignalinterface may detect a motion of a target, and the motion sensor mayobtain a first signal. For example, the motion sensor may detect andobtain a first signal associated with the flexing of an arm. In thisexample, the arm is the target from which signals can be detected.

In 312, the wearable biosignal interface may process the first signalobtained by the motion sensor and may extract a characteristic. Forexample, wearable biosignal interface may extract the magnitude of thefirst signal corresponding to a characteristic associated with a speedat which an arm is flexed.

In 313, the wearable biosignal interface may determine whether themagnitude of the first signal is greater than a first threshold value.For example, the wearable biosignal interface may determine a magnitudeof a first signal obtained in response to a user moving a muscle toactually operate an external device to be the first threshold value, andmay compare the first threshold value to magnitudes of the obtainedfirst signals.

Also, in 313, the wearable biosignal interface may identify an intervalduring which the magnitude of the first signal is less than or equal tothe first threshold value.

In response to a determination that the magnitude of the first signal isgreater than the first threshold value, for example, in a ‘Yes’direction from 313, the wearable biosignal interface may ignore thesecond signal obtained in the same interval during which the firstsignal is obtained. Also, the wearable biosignal interface may re-obtainthe first signal in 311.

Conversely, in response to a determination that the magnitude of thefirst signal is less than or equal to the first threshold value, forexample, in a ‘No’ direction of 313, the wearable biosignal interfacemay proceed to 323, as described later. The wearable biosignal interfacemay determine whether the second signal is valid based on a result ofcomparing the magnitude of the second signal obtained in the sameinterval during which the first signal is obtained to the secondthreshold value.

If the magnitude of the second signal is less than the second thresholdvalue, in 321, a biosignal sensor of the wearable biosignal interfacemay detect and may obtain a second signal from the target. For example,the biosignal sensor may obtain the second signal in response todetecting a tenseness of the muscles of the arm due to a flexing of thearm. The second signal may be obtained from the biological informationdetected by the biosignal sensor in 320.

In 322, the wearable biosignal interface may process the second signalobtained by the biosignal sensor 320 and may extract a characteristic ofthe second signal. For example, the wearable biosignal interface mayextract a magnitude of the second signal corresponding to acharacteristic associated with the tension in the flexed arm.

In 323, the wearable biosignal interface may determine whether themagnitude of the second signal is greater than a second threshold value.For example, the wearable biosignal interface may determine a referencevalue of the magnitude of the second signal, which may be a valuableinformation for determining the second threshold value, and may comparethe second threshold value to magnitudes of the obtained second signals.In 323, the wearable biosignal interface may determine a signal obtainedin the identified interval during which the magnitude of the firstsignal is less than or equal to the first threshold value to be a validsecond signal.

In the event that the magnitude of the second signal is less than orequal to the second threshold value, for example, a ‘No’ direction of323, the wearable biosignal interface may ignore the obtained secondsignal irrespective of a determination made in 313. Also, the wearablebiosignal interface may re-obtain the second signal in 321.

Conversely, in the event that the magnitude of the second signal isgreater than the second threshold value, for example, in a ‘Yes’direction of 323, the wearable biosignal interface may ultimatelydetermine the second signal to be valid based on a result ofdetermination in 313 and may proceed to 330 to execute the predeterminedcommand.

Operations described in the foregoing include using a motion sensor toobtain a first signal in 311, and using a biosignal sensor to obtain asecond signal in 321. However, it may be possible to perform 321 priorto or concurrent with 311.

In 330, the wearable biosignal interface may execute a command based onthe second signal determined to be valid. In 330, the wearable biosignalinterface may operate in an active mode and may allow an external deviceto be controlled based on the second signal. Using the second signalthat is determined to be valid, the wearable biosignal interface mayoperate an external device such as a mobile device, a TV screen, a DVDplayer, a radio, a heating thermostat, a vehicle door and the like.

Hereinafter, operations of a wearable biosignal interface 100 accordingto another example will be described with reference to FIG. 4.

FIG. 4 is a flowchart illustrating an example of an operation method ofa wearable biosignal interface 100.

In 410, the wearable biosignal interface 100 may detect a motion of atarget 105 of FIG. 1 and may obtain a first signal. The first signal maybe, for example, an acceleration signal, a rotation signal, a bearingsignal, a coordinate signal, and the like, that is associated with avelocity variance based on the motion of the target 105. In 410, thewearable biosignal interface 100 may monitor, using a motion sensor 110of FIG. 1, the motion of the target 105 and may receive the first signalto perceive a movement involved with the motion. For example, thewearable biosignal interface 100 may identify a gesture performed by thetarget 105 in response to obtaining a biosignal, and may obtain thefirst signal associated with the identified gesture.

For example, the motion sensor 110 may include an acceleration sensor.By applying integral calculus, the motion sensor 110 may convert anacceleration signal obtained by the acceleration sensor as the firstsignal into its velocity component. Based on the calculation, thewearable biosignal interface 100 may numerically indicate a magnitude ofa motion of the target.

For example, in the event that the target 105 is an arm that is flexed,the wearable biosignal interface 100 may obtain the first signalassociated with an “arm motion” based on the flexing of the arm. Also,the wearable biosignal interface 100 may measure the magnitude of theobtained first signal and may measure a velocity magnitude of the “armmotion.”

The motion sensor 110 may include a gyrosensor. For example, using thegyrosensor, the wearable biosignal interface 100 may measure a rotationsignal corresponding to the first signal.

In one example, target 105 may be an arm, and the arm may be performinga large rotation. The wearable biosignal interface 100 may obtain thefirst signal associated with the arm rotation based on the detectedmovement of the arm. Also, the wearable biosignal interface 100 maymeasure the magnitude of the obtained first signal and/or may measurethe magnitude of the anglular velocity of the arm rotation.

The motion sensor 110 may include a geomagnetic sensor or a GPS sensor.Using the geomagnetic sensor or the GPS sensor, the motion sensor 110may measure a bearing signal or a coordinate signal corresponding to thefirst signal.

According to an example, the motion sensor 110 may be fixed to a form ofa bracelet fastened onto the target 105, along with a biosignal sensor120.

The wearable biosignal interface 100 may be in contact with the target105 and may obtain a second signal from the target 105. In this example,the second signal may be a biosignal associated with biologicalinformation such as muscle contraction and muscle relaxation that isoccurring in the target 105. The second signal may be abio-electric/magnetic signal, a bio-impedance signal, and/or abio-mechanical signal generated in association with a muscle movement ormuscle tone.

In 420, the wearable biosignal interface 100 may be in contact with thetarget 105 through the biosignal sensor 120 and may obtain the secondsignal generated by at least one of muscle contraction and musclerelaxation. In an example in which the target 105 is a wrist, thewearable biosignal interface 100 may detect the second signal generatedby the muscle contraction or muscle relaxation of the wrist.

The target 105 may be, for example, a wrist, a forearm, a face, a neckand the like of a living being. The body part may include a muscle thatgenerates the second signal.

The biosignal sensor 120 may include at least one biosensor detectingthe second signal from a muscle of the target 105 and may monitorcontraction or relaxation of the muscle. The biosensor may be a photosensor, a piezoelelctric sensor, a force sensor, an EMG sensor, and thelike by using the at least one biosensor.

For example, the biosignal sensor 120 may include the photo sensor.Using the photo sensor, the wearable biosignal interface 100 may obtainthe second signal associated with a state of the target 105, based onlight scattering.

The biosignal sensor 120 may include a piezoelelctric sensor or a forcesensor. Using the piezoelelctric sensor or the force sensor, thewearable biosignal interface 100 may obtain the second signal associatedwith an extension and/or contraction state of the target 105.

The biosignal sensor 120 may include an EMG sensor. Using the EMGsensor, the wearable biosignal interface 100 may obtain the secondsignal associated with a muscle contraction or relaxation of the target105.

The biosignal sensor 120 may be affixed to a bracelet fastened onto thetarget 105, along with a motion sensor 110, as illustrated in FIG. 1. Inthis example, a sensing surface of the biosignal sensor 120 may beaffixed to the bracelet to be in a direct contact with the skin of thetarget 105. On the sensing surface, one or more biosensor may bearranged to detect a second signal generated from the target 105. Forexample, the bracelet may detect, using the biosignal sensor 120,various forms of second signals such as a bio-electric/magnetic signal,a bio-impedance signal, and a bio-mechanical signal associated with thetarget 105.

The bracelet may be fastened onto the target 105, wrapping around theskin that covers a wrist muscle. For example, the bracelet may befastened onto the target 105 by covering the wrist muscle with aspecialized area such as the sensing surface of the bracelet on whichthe one or more biosignal sensor 120 is disposed. Using the one or morebiosensor, the biosignal sensor 120 may collect the second signalthroughout an entire area of the wrist muscle of the target 105.

In 430, the wearable biosignal interface 100 may determine a validity ofthe second signal based on the first signal. In 430, the wearablebiosignal interface 100 may determine whether the second signal isgenerated by an intentional motion of the target 105 or incidentallygenerated by an unintentional or spontaneous motion of the target 105.

The wearable biosignal interface 100 may determine the second signal tobe valid in the event that the magnitude of the first signal satisfies afirst threshold value.

Here, the first threshold value may be a reference value used todetermine the intentional motion of the target 105. The first thresholdvalue may be determined as an average value of magnitudes of the firstsignals obtained while a user moves a muscle for an actual operation.

The wearable biosignal interface 100 may determine the first thresholdvalue based on a magnitude of the second signal to be obtained. Forexample, the wearable biosignal interface 100 may determine the firstthreshold value for operation involving a large motion of the target 105to be greater in proportion to the magnitude of the second signal; thus,the second signal generated by the intentional motion of the target 105may not be ignored due to a threshold value determined to be small.

The wearable biosignal interface 100 may determine the first thresholdvalue for a quick display shift operation of a display apparatus forwhich a relatively greater second signal is generated to be greater thanthe first threshold value for an ON/OFF operation of an illuminationapparatus for which a relatively smaller second signal is generated.

To determine a validity of the second signal, the wearable biosignalinterface 100 may identify interval during which the magnitude of thefirst signal is less than or equal to the first threshold value and maydetermine a signal, among the second signals, obtained in the identifiedinterval to be a valid second signal. The wearable biosignal interface100 may determine the second signal obtained in the interval duringwhich the magnitude of the first signal is less than or equal to thefirst threshold value and a small motion of the target 105 is determinedto be valid.

The wearable biosignal interface 100 may determine the second signal tobe invalid, irrespective of the first signal, in the event that themagnitude of the obtained second signal does not satisfy a secondthreshold value. The second threshold value may be a reference valueused to determine the second signal that is valuable as information. Thesecond threshold value may be determined as an averaged minimum valueobtained a user moves a muscle for an actual operation. For instance,the second threshold value may be determined from historic valuesobtained based on many actual operations performed by a target.

In the event that the magnitude of the obtained second signal is lessthan or equal to the second threshold value, the wearable biosignalinterface 100 may determine whether the target 105 moved intentionallyfor operation to be indefinite and accordingly, invalidate the secondsignal. Conversely, in the event that the magnitude of the second signalis greater than the second threshold value, the wearable biosignalinterface 100 may further determine whether the magnitude of the firstsignal satisfies the first threshold value and may determine thevalidity of the second signal.

Based on a result of the determination, in the event that the secondsignal is determined to be valid, the wearable biosignal interface 100may operate in an active mode and may allow an external device to becontrolled by the second signal. The external device may be a generalterm for devices controlled by a command signal, such as a mobiledevice, a TV screen, a DVD player, a radio, a heating thermostat, avehicle door, and the like. Using the wearable biosignal interface 100,the command signal may be generated based on the valid second signal.

For example, in the event that the magnitude of the first signal is lessthan or equal to the first threshold value, and the magnitude of thesecond signal exceeds the second threshold value, the wearable biosignalinterface 100 may shift a mode of the wearable biosignal interface 100to the active mode and may allow the external device to be controlledbased on the second signal; thus, the accuracy in determining anintention of a user may be improved.

To control the external device after the shift to the active mode, thewearable biosignal interface 100 may transmit the command signal basedon the valid second signal to an appliance such as a TV, an airconditioner, a computer, a refrigerator, and the like, or to a livingenvironment controlling device such as a light, a curtain, a window, adoor lock device, and the like. The transmission of the commend signalenables the external device to perform a control operation such as anON/OFF operation and an open/close operation, requested by the commandsignal.

The wearable biosignal interface 100 may use the valid second signal asa signal for a remote controller of a vehicle to start the vehicle, oras an identification (ID) signal to make a payment.

The wearable biosignal interface 100 may use the valid second signal asa signal for interactive control of a computer, or to edit a file storedon the computer or move a page for a presentation.

The wearable biosignal interface 100 may invalidate a biosignalgenerated by the unintentional or spontaneous motion of the target 105to optimally avoid a control error for the external device.

The wearable biosignal interface 100 may identify a biosignalexclusively generated during the state in which the target 105 is in acertain level of stability and may use the biosignal to control theexternal device. By using the biosignals genereated during a stablestate, it is possible to determine an intention of a user with improvedprecision.

Program instructions to perform a method described herein, or one ormore operations thereof, may be recorded, stored, or fixed in one ormore computer-readable storage media. The program instructions may beimplemented by a computer. For example, the computer may cause aprocessor to execute the program instructions. The media may include,alone or in combination with the program instructions, data files, datastructures, and the like. Examples of non-transitory computer-readablestorage media include magnetic media, such as hard disks, floppy disks,and magnetic tape; optical media such as CD ROM discs and DVDs;magneto-optical media, such as optical discs; and hardware devices thatare specially configured to store and perform program instructions, suchas read-only memory (ROM), random access memory (RAM), flash memory, andthe like. Examples of program instructions include machine code, such asproduced by a compiler, and files including higher level code that maybe executed by the computer using an interpreter. The programinstructions, that is, software, may be distributed over network coupledcomputer systems so that the software is stored and executed in adistributed fashion. For example, the software and data may be stored byone or more computer readable storage mediums. Also, functionalprograms, codes, and code segments that accomplish the examplesdisclosed herein can be easily construed by programmers skilled in theart to which the examples pertain based on and using the flow diagramsand block diagrams of the figures and their corresponding descriptionsas provided herein. Also, the described unit to perform an operation ora method may be hardware, software, or some combination of hardware andsoftware. For example, the unit may be a software package running on acomputer or the computer on which that software is running.

While this disclosure includes specific examples, it will be apparent toone of ordinary skill in the art that various changes in form anddetails may be made in these examples without departing from the spiritand scope of the claims and their equivalents. The examples describedherein are to be considered in a descriptive sense only, and not forpurposes of limitation. Descriptions of features or aspects in eachexample are to be considered as being applicable to similar features oraspects in other examples. Suitable results may be achieved if thedescribed techniques are performed in a different order, and/or ifcomponents in a described system, architecture, device, or circuit arecombined in a different manner and/or replaced or supplemented by othercomponents or their equivalents. Therefore, the scope of the disclosureis defined not by the detailed description, but by the claims and theirequivalents, and all variations within the scope of the claims and theirequivalents are to be construed as being included in the disclosure.

The invention claimed is:
 1. A wearable biosignal interface, comprising:a motion sensor configured to obtain a first signal based on a motion ofa target; a biosignal sensor configured to be disposed on the target andobtain a second signal from the target; and a determination controllerconfigured to perform, in response to a magnitude of the first signalbeing less than or equal to a first threshold, a function of thewearable biosignal interface using a portion of the second signalcorresponding to an interval during which the magnitude of the firstsignal is less than or equal to the first threshold.
 2. The wearablebiosignal interface of claim 1, wherein the determination controller isconfigured to determine the second signal to be valid in response to themagnitude of the first signal not satisfying the first threshold.
 3. Thewearable biosignal interface of claim 1, wherein the determinationcontroller is configured to: identify the interval during which themagnitude of the first signal is less than or equal to the firstthreshold; and determine a signal, among a plurality of second signalsobtained by the biosignal sensor in the identified interval, to be avalid second signal.
 4. The wearable biosignal interface of claim 2,wherein the determination controller is configured to determine thefirst threshold based on a magnitude of the second signal.
 5. Thewearable biosignal interface of claim 1, wherein the determinationcontroller is configured to determine the second signal to be invalid,irrespective of the first signal, in response to the magnitude of thesecond signal not satisfying a second threshold.
 6. The wearablebiosignal interface of claim 1, wherein: in response to a determinationto perform the function of the wearable biosignal interface, thedetermination controller is configured to perform the function; and thefunction of the wearable biosignal interface includes the determinationcontroller operating in an active mode to control an external devicebased on the second signal.
 7. An operation method of a wearablebiosignal interface, the method comprising: using a motion sensor toobtain a first signal based on a motion of a target; using a biosignalsensor disposed on the target to obtain a second signal; and performing,in response to a magnitude of the first signal being less than or equalto a first threshold, a function of the wearable biosignal interfaceusing a portion of the second signal corresponding to an interval duringwhich the magnitude of the first signal is less than or equal to thefirst threshold.
 8. The method of claim 7, wherein the determining ofthe validity comprises: determining the second signal to be valid inresponse to the magnitude of the first signal not satisfying the firstthreshold.
 9. The method of claim 7, wherein the determining of thevalidity comprises: identifying the interval during which the magnitudeof the first signal is less than or equal to the first threshold; anddetermining a signal, among second signals obtained by the biosignalsensor in the identified interval, to be a valid second signal.
 10. Themethod of claim 8, wherein the determining of the validity furthercomprises: determining the first threshold based on a magnitude of thesecond signal.
 11. The method of claim 8, wherein the determining of thevalidity comprises: determining the second signal to be invalid,irrespective of the first signal, in response to a magnitude of thesecond signal not satisfying a second threshold.
 12. The method of claim7, further comprising: operating in an active mode and controlling anexternal device based on the second signal, in response to the secondsignal being determined to be valid.
 13. The wearable biosignalinterface of claim 1, wherein the second signal includes biologicalinformation obtained by one or more biosensor in contact with skin ofthe target.
 14. The method of claim 8, wherein the second signalincludes biological information obtained by one or more biosensor incontact with skin of the target.
 15. An apparatus comprising: a motionsensor configured to detect a movement signal corresponding to amovement of a target; a second sensor configured to detect a biologicalsignal corresponding to a biological information of the target; and acontroller configured to: determine an interval of stability in which amagnitude of the movement signal is less than or equal to a movementsignal threshold, determine a portion of the biological signal detectedin the interval of stability, and identify a command for controllinganother device using the portion of the biological.
 16. The apparatus ofclaim 15, wherein: the interval is determined by extracting the movementsignal based on the movement of the target; and the biological signal isextracted from the biological information obtained by the second sensor,the second sensor comprising one or more biosensors.
 17. The apparatusof claim 16, wherein the interval corresponds to a time duration inwhich the magnitude of the first processed signal is less than or equalto the movement signal threshold.
 18. The apparatus of claim 16, furthercomprising a transmission unit configured to transmit the command to theanother device, wherein the determination controller is configured toidentify the command based on the portion of the biological signal. 19.The apparatus of claim 18, wherein, in response to a determination thatthe magnitude of the movement signal is greater than the movement signalthreshold, the apparatus is configured not to transmit a command basedon the portion of the biological signal.
 20. The wearable biosignalinterface of claim 1, wherein the determination controller is configuredto perform the function based on a comparison between the first signaland a first threshold.